The title is a reference to the phenomenon that occurred in the mid-1960s when rock and pop music acts from the United Kingdom, as well as other aspects of British culture, became popular in the United States, and significant to the rising "counterculture" on both sides of the Atlantic.

Much like John during Mary's death, Mary has developed a romantic relationship with someone else, specifically with Arthur Ketch. This makes it the first time she had a sexual encounter with anyone in almost three decades.

Lucifer calls Michael his "little bro". It has previously been established throughout Season 5 that Michael is the older of the two. This same error was made in Hell's Angel, an episode also written by the same writers.